1. Field of Invention
The present invention relates to a lighting apparatus and a control method thereof.
2. Related Art
The light emitting diode (LED) can be driven by a suitable current to emit desired light, and the brightness of the light emitted from the LED can be adjusted by controlling the current flowing therethrough. In general, the brightness of the LED can be adjusted by the way of continuous current dimming or pulse width modulation (PWM) dimming. Comparing these two dimming methods, the PWM dimming has the advantages of lower dimming depth and less color change, so it is widely used now. However, due to the variations in the both characteristics of LED and the output of power supply, it maybe results in the variation in the amplitude of LED at PWM dimming operation. Therefore, it is an important subject to provide a current with stable amplitude to the LED when using the PWM dimming method.